The Layer Manager Window

Overview

The layer manager is used control what content is shown in the current image view and how it is displayed.

You can open the layer manager tool window from the View / Tool Windows / Layer Manager menu or by clicking the icon in the tool bar. A layer can be shown or hidden by using the check box left to the layer name. 

Any number of layers may be open at one time. Each layer will have a rendering order, and much like a painter’s algorithm, will be drawn on top of each other. The user willhave control over the layer ordering and the translucency of the images. Finer visibility control can be achieved by selecting a layer and using the Transparency slider. Visibility changes will directly take effect in the image view.

Layer manager tool window

Functions

Add layer: Opens the Add Layer assistant window which lets you add a new layer to the current view.

Remove layer: Removes the selected layer. Note that not all layers can be removed.

Edit layer: Opens the Layer Editor tool window which lets you alter the display properties of the selected layer.

Move up: Moves the selected layer up so that it is displayed on top of all layers following it in the list.

Move down: Moves the selected layer down so that it is displayed underneath of all overlying layers in the list.

Move left: Moves the layer into the parent group (if any).

Move down: Moves the layer into a child group (if any).

Layer Editors

Layer editors lets you alter layer properties in order to control the display of layer data. Different layer types have different layer editors. The following screenshot shows the layer editor of the pin layer:

Layer editor tool window

Changes to the properties in this window are directly propagated to the layer selected in the layer manager and display updates will occur immediately in the current image view.

Adding Layers

The Add Layer assistant window shows a number of layer sources. It depends on the type of the current image view which layer sources are present in this list. 

In addition to the raster data products, the DAT will be able to load and display vector data as layers. This will prove helpful for overlaying shoreline, political boundaries, navigational charts, etc., and using this data to mask land or water areas.

The following standard layers are always usable:

• ESRI Shapefile - Overlays an ESRI shapefile read from a file.
• Image from File - Overlays any image read from a file.
• Image of Band / Tie-Point Grid - Overlays images of bands or tie-point grids of other products currently opened.
• Layer Group - Creates a group in which you can freely organise other layers and groups.

Layer sources which are restricted to special image views are:

• Image from Web Map Service (WMS) - Downloads a thematic image map layer from a dedicated internet WMS. Applicable to map-projected (geo-referenced) views only. A good list of public services is provided at http://www.skylab-mobilesystems.com/en/wms_serverlist.html.
• Wind Speed from MERIS ECMWF annotation data - Displays wind speed vectors. Applicable to MERIS L1b/L2 band views only.

The 'Add Layer' dialog

Select a layer source and press > Next. Depending on the type of layer selected, the assistant window will guide you through one or more option pages. Once the Finish button is enabled, you can add the new layer to the current image view.

Layer manager tool view after adding an ESRI shapefile layer